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                The DB Handle
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            <h2 class="title" style="clear: both"><a id="dbcreate"></a>db_create</h2>
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      <pre class="programlisting">#include &lt;db.h&gt;

int db_create(DB **dbp, DB_ENV *dbenv, u_int32_t flags);  </pre>
      <p>
        The <code class="function">db_create()</code> function creates a <a class="link" href="db.html" title="Chapter 2.  The DB Handle">DB</a> 
        structure that is the handle for a Berkeley DB database. This function allocates memory for the
        structure, returning a pointer to the structure in the memory to which 
        <span class="bold"><strong>dbp</strong></span> refers.  To release the allocated memory and 
        discard the handle, call the <a class="xref" href="dbclose.html" title="DB-&gt;close()">DB-&gt;close()</a>, 
        <a class="xref" href="dbremove.html" title="DB-&gt;remove()">DB-&gt;remove()</a>, 
        <a class="xref" href="dbrename.html" title="DB-&gt;rename()">DB-&gt;rename()</a>, or 
        <a class="xref" href="dbverify.html" title="DB-&gt;verify()">DB-&gt;verify()</a> methods.
    </p>
      <p>
        DB handles are free-threaded if the 
        <a class="link" href="envopen.html#envopen_DB_THREAD">DB_THREAD</a> flag is specified to 
        the <a class="xref" href="dbopen.html" title="DB-&gt;open()">DB-&gt;open()</a> method when the database is opened or 
        if the database environment in which the database is opened is free-threaded. The handle 
        should not be closed while any other handle that refers to the database is in use; for 
        example, database handles must not be closed while cursor handles into the database remain 
        open, or transactions that include operations on the database have not yet been committed 
        or aborted.  Once the <a class="xref" href="dbclose.html" title="DB-&gt;close()">DB-&gt;close()</a>, 
        <a class="xref" href="dbremove.html" title="DB-&gt;remove()">DB-&gt;remove()</a>, 
        <a class="xref" href="dbrename.html" title="DB-&gt;rename()">DB-&gt;rename()</a>, or
        <a class="xref" href="dbverify.html" title="DB-&gt;verify()">DB-&gt;verify()</a> 
        methods are called, the handle may not be accessed again, regardless of the method's return.
    </p>
      <p>
        The DB handle contains a special field, <code class="literal">app_private</code>, 
        which is declared as type <code class="literal">void *</code>. This field is provided for the use
        of the application program. It is initialized to NULL and is not further used by 
        Berkeley DB in any way.
    </p>
      <p>
        The <code class="literal">db_create</code> function returns a non-zero error value on failure
        and 0 on success.
    </p>
      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp49437224"></a>Parameters</h3>
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        <div class="sect3" lang="en" xml:lang="en">
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              <div>
                <h4 class="title"><a id="idp49437448"></a>dbp</h4>
              </div>
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          <p>
                The <span class="bold"><strong>dbp</strong></span> parameter references the
                memory into which the returned structure pointer is stored.
            </p>
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        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
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              <div>
                <h4 class="title"><a id="idp49432784"></a>dbenv</h4>
              </div>
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          <p>
                <span>If the <span class="bold"><strong>dbenv</strong></span> parameter is NULL,</span> 
                 
                the database is standalone; that is, it is not part of any Berkeley DB
                environment.
            </p>
          <p>
                <span>
                    If the <span class="bold"><strong>dbenv</strong></span> parameter is not NULL,
                </span>
                
                the database is created within the specified Berkeley DB environment. 
                The database access methods automatically make calls to the other
                subsystems in Berkeley DB, based on the enclosing environment.  For
                example, if the environment has been configured to use locking, the
                access methods will automatically acquire the correct locks when
                reading and writing pages of the database.
            </p>
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        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
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              <div>
                <h4 class="title"><a id="idp49445520"></a>flags</h4>
              </div>
            </div>
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          <p>
                  The <span class="bold"><strong>flags</strong></span> parameter must be set to 0 or the following value:
             </p>
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            <ul type="disc">
              <li>
                <p><a id="dbcreate_DB_XA_CREATE"></a>
                                <code class="literal">DB_XA_CREATE</code>
                            </p>
                <p>
                                Instead of creating a standalone database, create a database intended
                                to be accessed via applications running under an X/Open conformant
                                Transaction Manager.  The database will be opened in the environment
                                specified by the OPENINFO parameter of the GROUPS section of the
                                ubbconfig file.  See the <a href="../../programmer_reference/xa_xa_intro.html" class="olink">XA Introduction</a> section in the Berkeley DB Reference Guide for
                                more information.
                            </p>
              </li>
            </ul>
          </div>
        </div>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
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            <div>
              <h3 class="title"><a id="idp49400640"></a>Errors</h3>
            </div>
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        <p>
                        The <code class="function">db_create()</code> function may fail and return one of the following non-zero
                         errors:
                    </p>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp49413856"></a>EINVAL</h4>
              </div>
            </div>
          </div>
          <p>
                An invalid flag value or parameter was specified.
            </p>
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      <div class="sect2" lang="en" xml:lang="en">
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            <div>
              <h3 class="title"><a id="idp49433104"></a>Class</h3>
            </div>
          </div>
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        <p>
            <a class="link" href="db.html" title="Chapter 2.  The DB Handle">DB</a>
        </p>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp49256424"></a>See Also</h3>
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        <p>
            <a class="xref" href="db.html#dblist" title="Database and Related Methods">Database and Related Methods</a> 
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